Electric toaster



ELECTRIC TOASTER Original F iied April 5, 1933 3 Sheets-Sheet l w I dINVENTOR ATTORNEY 25, 1939. LAvE-NBURG I Re. ZLOGO :ELECTR'IC' TOASTERnig ina l Filed Apz-il 5, 1935 3- Sheets-Sheet 2 INVENTOR ATTORNEY G.LAVENBURG Aprfl 25, 1939.

ELECTRIC TOASTER Original Filed April 5, 1933 3 Sheets-Sheet 5 .illhnnHwu nv l n.

INVENTOR ATTORNEY Reiuued Apr. 25, 1939 UNITED STATES ELECTRIC rossraaGeorge Lavenburg, New York, N. Y.

Original No. 2.046.411, dated July '1', 1936, Serial No. 664,493, April5, 1933. Application for reissue December 1a, 1938, Serial No. 246,231

11 Claims.

This invention relates to new and useful improvements in electrictoasters and particularly to toasters of the so-called automatic type inwhich the operation once initiated is automati- 5 cally terminated uponthe expiration of a predetermined period of time.

The objects of the invention are the provision of a simple, rugged andinexpensive timing mechanism; the initiation of all operations by asingle 0 manual operation, e. g., by pulling down a single lever; meanswhereby the automatic timing of the toaster may be at times delayed,suspended, speeded up, or entirely replaced by manual operation withoutthe necessity of performing any 15 special operations; the provision ofa toaster'in which the bread gradually appears in view from the oven andcontinually moves during the toasting.

With these objects in view, I provide a timingdevice which ismechanically at all times disconnected from the toaster and which in thepresent embodiment of the invention consists of a motor deliveringimpacts at -a movable member which, after traveling a certain distance,terminates the toasting operation. In the present case, the impacts aredelivered by means of a steel ball which the motor hurls against themovable member. The movable member is held in its advanced positionandthe ball is returned to the motor by gravity.

The bread and oven are gradually and continuously moved with respect toone another, preferably by raising the bread under the control of saidmovable member and the toasting operation is terminated when the movablemember reaches a predetermined position. Owing to this continuousmotion, the bread will be evenly toasted throughout its surface and theapparatus is never subjected to sudden jars. Besides, the operator maybefore the completion of the toasting determine its suihciency. I

The operation is initiated by a single manual operation, e. g., bypulling down a handle. This will lower the bread within the oven,advance said member into its starting position, close the circuits ofthemotor and the heating elements and thus start both the toasting andtiming opera-- (CI. ISL-16) tion with the bread projecting from the ovenand said circuits interrupted.

These and other features of the invention will more fully appear fromthe following description of a preferred embodiment thereof and the ap-'I pended claims. Obviously, thesedetails may be changed withoutdeparting from the spirit of the invention, and some of these featuresmay be embodied in other types, of toasters.

In the drawings, Fig. 1 is a vertical cross-section of a toaster; Fig. 215a top plan view with parts of'the cover removed;

Fig. 3 is an end elevation with parts of the cover removed; 15

Fig. 4 is a perspective view of the oven section:

Fig. 5 is a sectional view along lines 5--5 of Fig. 2:

Fig. 6 is a sectional view along lines 65 01' Fig. 5; and h Fig. 7 is acircuit diagram.

The toaster consists of an oven and an operating mechanism, the formerenclosed within a casing I and the latter within a casing 2. Bothcasings are mounted on a common base 3 which is open below the oven, asindicated at 4, so that bread crumbs may fall through into a removabledrawer 5. The top of theoven is covered by a plate 6 provided with fourlongitudinal slots or openings 1 in alignment with vertical ovencompartments and of a size to permit free passage of 'a slice of bread.A slice of bread inserted through these openings will be guided betweenguard wires 8 suspended on both sides of each oven compartment fromsquared rods 9 one end of which rests in notches l0 provided in a railll fastened to a side wall ofthe casing I. The other ends of the bars 9are supported in notches of a rail I! mounted on a side wall I! of theoven which separates the oven from the chamber enclosing the timing andcontrolling mechanism. The bars 9 are arranged in pairs, the bars ofeach pair being spaced from one another to hold the upper edge of aheating element composed of two notched mica sheets ll on which aresistance wire I5 is wound. The two ends of the resistance wireterminate in metal tabs It at the bottom of the mica sheets ll, themetal tabs being held in connecting clips l1 and II, respectively,mounted on conductor rails l9 and 29 carried on posts II on the baseplate 9 but insulated therefrom. Current is suppliedtotheraiis "andllthmghbindlngposta 22. Itwinbenotedtbatthebus Iwlththe 31m!!! 8 are andthe'beating elements are also removably mounted in the clips so as toinsure quick and easy removal and change which 'can be effected simplyby removing the oven top 6. 4

The guards 6 prevent the bread from mining in contact with the heatingelements, and strips like 23 depending from the rail keep the bread fromsliding into contact with the side wall of the casing I. Each slice ofbread will rest on a bread platform 24, the bread platform havingprojections 25 between adjacentguard wires 6 to prevent slipping of thebread on the-platform and into contact with the heating element betweenadjacent guard wires. a

Each bread platform 24 has an extension 26. projecting through alongitudinal slot in the separating wail l3, all the extensions 26 beingfastened to a crossbar 21. In their normal position, the bread platformsare in the position indicated in dotted lines in Fig. 1. After a sliceof bread has been inserted within each oven compartment and is restingon its platform 24, the attendant lowers the bread entirely within theoven and starts the operation of thetoaster by grasping a handle 26andmoving it from the position indicatedin dotted lines in Fig. 1 intothe position indicated in full lines. The handle projects through a slotin the top of the casing 2. Its forked end 26 within the casing 2 isfastened to the two ends of a cross piece 36. The cross piece 36 isadaptedto slide back and forth between the top edge of a trough 3| and acover plate 32 which is straddled by a bent-up portion 33 of the crosspiece 36. Fastened to the lower end of the cross piece 36 there is aslider 34 within the trough 3| and the two ends of the cross piece areengaged at their under side on both sides of the trough 3| by levers 35and 36. The ends of these levers are pivotally mounted on a shaft 31.which is encircled by a double wound spring 33, a central tongue '36 ofwhich bears against a post 46" mounted on the base plate 3. The two freeends 4| and 42 of the spring 36 engage'the levers 35 and 36 and urgethem upwards against the cross piece 36. When therefore the operatormoves the handle as above stated. the cross piece 36 will depress levers35 and 36 against the tension of spring 36.

During the forward movement of the slider 36 the bread platforms arelowered by their own weight and by the weight of the bread slices, thepositioning of the bread platforms being controlled by a flat cable 43,one end of which is attached to the upright piece 33 of the slider at 44and'the other end -of which is attachedto the cross bar 21 at 45 nearthe center thereof. The cable 43 passes over an idler pulley 46 mountedon a port 41 on the base plate 3 and on a pulley 46 mounted in a bracket49 on the oven wall l3 above the slots 21. The horizontal positioning ofthe .cross bar. 21 and of the bread platforms is insured by a sleeve 56fastened to each end of the cross bar 21. A post fastened to the baseplate 3 projects within each sleeve 56, the sleeves being free to slideup and down on these posts. Shortly after the cross piece 21 leaves itstop position a finger 62 projecting therefrom will tip a mercury switch53 from the position shown in dotted lines in Fig. 3 into the positionshown in' full lines. The mercury switch 52 is clamped in a bracket 54which may oscillate around a shaft 65 fastened to the separating walll3, said bracket 64 having a tongue 56 projecting into the path of thefinger 52 on the cross bar 21.

75 When the mercury switch is thus tipped it will close a circuit (Fig.7) from the power line K 66, through the first three resistances l5 inparallel, through conductors 6|, back to the other side of the powerline 66. A parallel circuit is closed through the mercury switch 53, avariable 5 resistance 62 and a motor 63, and a third parallel circuitthrough the last two resistances IS, a switch 64 and conductor 6|. Ifthe switch 64 (which is suitably mounted on the outside of the casing)is closed, all the resistances l5 will be 10 traversed by current and,depending on the setting of the variable resistance 62 (also suitablymounted on the outside of the casing), the motor 63 will start rotatingits shaft 65 at a certain speed. The various electrical connections aresuitably established by means of a terminal block 66, mounted on thebase plate 3.

The projecting shaft of the motor carries fan blades 61 to cool thecompartment within the casing 2 and at its end it carries an impeller 66having an angular cross section. The-impeller 66 is at right angles tothe trough 3| and blocks the open end thereof, but is spaced therefromsufliciently to permit free rotation. As indicated in Fig. 1, the trough3| is inclined towards the g5 impeller 66, the higher end of the troughbeingfastened at 69 to the upright which, as shown, forms a leg of'thecover plate 32.

As viewed from the motor side (Fig. 1), the shaft 65 of the electricmotor rotates in a clock- 39 wise direction and therefore the impeller66 will drive steel ball 16 towards the slider 34 (see Fig. 5). Owing tothe inclined floor of the trough 3| the steel ball 16 will tend to rollback into contact with the impeller 66, the ball being prevented 35 fromfalling out because its diameter is larger than the separation betweenthe impeller 66 and the'end of the trough 3|. Whenever the impeller 66delivers a blow to the ball it will'drive it to,- wards the slide 34,the trough 3| and its cover a plate 32 serving as a guide to keep theball moving between the impeller and the slide.

In response to each impact delivered to the slide 34 by the ball", theformer is caused to advance towards the left (Fig. 5), the impact beingsufflcient to overcome the frictional resistance between the slide andits trough, between the levers 35, 36 and the cross piece 36 which, asabove stated, is attached to the slide, and between the cable 43 andpulleys 46 and 46. However, once this frictional resistance overcomesthe force of the impact, the slide is held in its advanced position bythe levers 35 and 36 which, under the control of spring 36, rise step bystep during each advance step of the slide.

. While the slide'is thus driven bytheball 16 it will'draw upward bymeans of the cable 43, the cross bar 21 and the bread platforms 24attached thereto. The slices of bread resting on the bread platformswill therefore be continuously and w gradually moved out of the ovencompartments. During the travel past the incandescent resistance wiresI5, both sides of the bread slices will be toasted, and owing to thefact that the bread moves continuously with respect to the resistances,the toasting will be substantially uniform throughout the surfaces ofthe bread slices.

When during the upward travel of the cross bar 21 the finger 52 reachesthe-tongue 56 of the bracket 54 in which mercury switch 53 is sus-mpended, the latter will be tipped in a clockwise direction to open inits. contacts the circuitsv of the motor 63 and the heating elements|6.. Owing to its inertia. the motor will continue to rotate until thecross bar 21 is in a position where the II timed by means of therheostat 62 that just sumfinger 52 is above the tongue 85 of mercuryswitch bracket 84. The bread slices are now protruding through theopening 1 of the oven top' Q about 2 inches and may be removed by theattendant. At the beginning of the toasting operation the lower edge ofthe bread is preferably below the tab ii of the resistances, the samedistance as it is desired the bread will extend out of the casing at theend of the toasting operation.

The speed of rotation of the motor 63 is so cient time elapses betweenthe closing and opening of the circuits by the mercury switch 53 totoast the bread slices to the desired extent. Owing to the fact thatthere is no physical connection between the timing element constitutedby the motor and its shaft and the timed element constituted by theslider 34 and its associated equipment, and that there is no physicalconnection between the ball 10 and either the timed or timing elements,the attendant may at any time arrest, slow down, speed up, or entirelyeliminate the timing operation simply by grasping the handle 28. Throughthe handle the attendant can operate the timed element at will and thusmanually control the toasting operation since the impact of the ball 10is insuflicient to overcome such resistance. The attendant may, forinstance, when noticing that the protruding upper edges of the breadslices are insufllciently toasted, again move theslide 34 all the wayback to the right so as to permit it again being driven by the ball 10,

or he may simply arrest the further elevation of the bread pieces untilthey are more fully toasted. Again, the attendant may push the slide 3|to the left faster than it would be driven by the ball Ill. thusspeeding up the toasting operation. Since, as above stated, there is nophysical connection between the timing and timed elements, theseoperations by the attendant can be performed without the necessary ofoperating any clutches, shifting connections or the like and should forany reason the timing element fail to operate the toaster can be used asa manually operated device until the necessary repairs can be effected.

By opening the switch 64 the device can be used to toast two instead offour slices of bread.

It will be obvious to those skilled in the art that numerous changes canbe effected in the embodiment of the invention without departing fromthe spirit thereof. While the timing arrangement has particularadvantages in connection with toasters-it may be used for timing otheroperations and certain features of the toaster may be used incombination with other types of timing devices. Furthermore, while in mypreferred embodiment the bread is gradually and continuously moved withrespect to the resistance elements, some of the features of my inventionmay be embodied in toasters in which automatic bread toasting iseffected by different relative movements.

What is claimed is:

1. In an electric toaster, an oven, electric heating elements therein,an electric motor, .a shaft rotated by said motor, a movable elementphysically spaced from said shaft, a ball adjacent said shaft and movedin response to rotation thereof,

means for guiding said ball towards said movable element, meanscontrolled by said movable element for moving bread out of said oven,and circuits for said motor and heating elements also controlled'by saidmovable element.

2. In combination, an open-ended trough. a slider within said trough, aspring-pressed lever holding said slider against advancement, anelectric motor having a projecting shaft of angular cross sectionblocking the open end of said trough but spaced therefrom to allow freerotation, a ball within said trough having a larger diameter than thespacing betweensaid trough and shaft and moved in response to therotation of said shaft, and a circuit for said motor con trolled by saidslider.

3. In combination, an inclined trough open at its lower end and having acover plate spaced therefrom, a slider within said trough, a cross piececarried by said slider between the trough and its cover plate, twospring-pressed levers pivoted at one end bearing against the under sideof said cross piece, a handle attached to said cross piece, an electricmotor having a shaft, an impeller of angular cross section on said shaftand blocking the open end of said trough but spaced therefrom to allowfree rotation, a ball within said trough having a larger diameter thanthe spacing between said trough and impeller and moved in response tothe rotation of said impeller, and a circuit for said motor, and aswitch in said motor circuit controlled by said cross piece.

4. In an electric toaster, an oven having openings, electric heatingelements dividing said oven into compartments in alignment with saidopenings, a bread platform within each oven compartment, moving meansfor said platforms outside of said oven, an inclined open-ended trough,

-a slider within said trough, a spring-pressed lever for holding. saidslider against displacement, an electric motor having a shaft, animpeller of angular cross section on said shaft and blocking the openendof said trough but spaced therefrom to allow free rotation, a ballwithin said trough having a larger diameter than the spacing betweensaid trough and impeller and moved in response to the rotation of saidimpeller, circuits having a common branch for said motor andresistances, a variable resistance in the motor cir- 'cult, and a switchin said common branch confrom, a slider within said trough, a crosspiece carried by said slider between the trough and its cover plate, twospring-pressed levers pivoted at one end bearing against theunder sideof said cross piece, a handle attached to said cross piece,-

a cable having one end attached to the cross piece of the slider and theother to said bar, an electric ,motor having a shaft, an impeller ofangular cross section on said shaft and blocking the open end of saidtrough but spaced therefrom to allow free rotation, a ball within saidtrough having a larger diameter than the spacing between said trough andimpeller and moved in response to the rotation of said impeller,circuits having a common branch for said motor and resistances, a

variable resistance ,in the motor circuit, and a switch in said commonbranch controlled by said .bar interconnecting the platform extensionsbut only in one position thereof.

a. a toaster comprising electrical heatingmeans.aioodsupportadiaoentsaidheating means. a switch for circuit ofsaid heating means, a handle for moving said support from a normalposition to any oneoi a plurality of advanced positions, and means (orautomatically opening said switch after the lapse,

of varying intervals of time depending on the advanced position to whichthe support has been moved, said last mentioned means includingtrictional means ior holding said support in any advanced position and adevice for overcoming said frictional means.

7. A toaster comprising an oven, electric heat ing means associated withsaid oven, a food support adapted to be moved from a normal position toany one oi a plurality oi advanced posi- ,tions within said oven, andautomatic means for moving said support outwardly irom said oven duringthe toasting operation, said last mentioned means including frictionalmeans for holding said support in am advanced position and a device forovercoming said frictional means.

8. In a toaster, normally inactive electric heating means, a supportnormally holding tood near said inactive heating means. manual means formoving said support adjacent said heating means into any one or aplurality of advanced positions. means operative upon the moving of thesupport out of the normal position for closing a circuit for saidheating means, frictional means for holding said support in any advancedpodtion,

and automatic means including a device for ing said support outwardlyfrom said oven dur- 7 ing the toasting operation, a mercury switch iorcontrolling the circuit 01 said heating means. av

was mounting ior ms switch, means including said support for tiltingsaid switch in onedirection to close said circuit, said automatic meansincluding a timing mechanism having a slide with two ends, a. slideradapted to move along said slide' means for gradually advancing saidslider to one end of said slide, and means for gradually tilting saidswitch in the opposite direction to open said circuit as said slideradvances to said one end.

10. A bread toaster comprising an oven having a movable bread'support,an electric heat-' ing means associated with the said oven, a switch forcontrolling the circuit of the heating means,

a handleadapted to be moved from a normal 1 pomtion' to any one 01 aplurality oi advanced positions for lowering the bread within the ovenadjacent the said heating means and means, for automatically openingsaid switch after a lapse of various intervals of time depending uponthe advancedposition to which the handle has been moved, said lastmentioned means including frictional means for holding the handle in anyadvanced position, and a device for overcoming the frictional means.

11. A bread toaster comprising electrical heating means, a loud supportadjacent said heating means, .a switch for controlling the circuit ofsaid heating means. a handle movable to any of a plurality of positions,said handle having a controlling connection holding the food supportraised when the said handle is in one extreme position and enabling saidbread support to be lowered as the said handle is advanced tional means.7

I GEORGE LAVENBURG.

